Integrated cockpit door lock and access system

ABSTRACT

An electromechanical flight deck door locking system capable of functioning to keep a cockpit door locked in the event of an interruption in electrical power to the system. The flight deck door locking system includes a locking assembly including a locking component and a manually graspable handle for displacing the locking component. Further, the locking system includes an electronic control panel configured to receive data from an individual seeking access to the cockpit and for electrically locking and unlocking the locking assembly. The locking system also includes a mechanical locking assembly, such as a key lock, whereby a user can use a key to lock and unlock the door if electrical power to the system is unavailable.

FIELD OF THE INVENTION

This application is a divisional of U.S. patent application Ser. No.10/255,916 filed on Sep. 26, 2002. The disclosure of the aboveapplication is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to door locking systems, andmore particularly to an aircraft cockpit door locking system that allowsthe cockpit door to remain locked and functional in the event of a powershortage affecting the electronic components associated with the doorlocking system.

BACKGROUND OF THE INVENTION

Effectively controlling access to the cockpit of a passenger aircrafthelps to control numerous risks associated with unauthorized cockpitentry. Typically, aircraft personnel have controlled access to cockpitsthrough electronic locking mechanisms disposed on or in the cockpitdoor. Electronic locking systems typically involve solenoid systemscomprising an electric solenoid and a keypad, wherein the solenoidautomatically locks upon closing the door and unlocks upon a cabin crewmember entering an access code with the keypad.

While the electronic system effectively controls access, some situationscould arise where the effectiveness of the system may be compromised.For example, an individual might be able to traverse the security of theelectronic system by cutting the power supply conductors to the system,thus de-energizing the solenoid and unlocking the door. This scenariowould apply to those systems where power is being supplied to thesolenoid to hold it in an engaged, i.e., locked position. Furthermore,an individual might be able to traverse an electronic security system bywitnessing a cabin crew member enter an access code, and subsequentlyre-entering the same access code.

Thus, it would be desirable to provide an even safer, more securecockpit door locking system. More specifically, it would be desirable toprovide a locking system that eliminates the aforesaid risks of a purelyelectronic system in the event of a power shortage or unauthorized useof the access code. Furthermore, it would be desirable to have a doorlocking system that remains locked, yet otherwise operational, in theevent of an interruption of power to the components of the door securitysystem.

SUMMARY OF THE INVENTION

The present invention is directed to a cockpit door locking systemhaving an electromechanical locking assembly capable of maintaining adoor locking mechanism in its locked position in the event of a powershortage. One preferred embodiment of the present invention includes anelectronic control panel for controlling the cockpit door lockingassembly when supplied with electrical power. The locking assembly issituated in or on the cockpit door and includes a locking component,such as a latch or a dead bolt, that remains locked whether or not thesystem remains energized. The electronic control panel further controlsa user input device adapted to receive an access code from a cabin crewmember. The electronic control panel thereafter informs the cockpit crewthat a cabin crew member has requested access, and the cockpit crew canchoose to grant or deny access. The cockpit door locking system alsoincludes a mechanical key lock assembly that requires engagement by aphysical key which can: (1) lock or unlock the locking assembly in theevent of a power shortage; and (2) act as a substitute for the securitycode when power is available for system operation.

The cockpit door locking mechanism of the present invention thereforeprovides the benefit of restricting access to the cockpit of an aircraftthrough the use of a robust electromechanical system. Importantly, thesystem is capable of maintaining the cockpit door in a locked conditionin the event of a power shortage.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the following detailed description and specificexamples discussed herein are only provided to illustrate the inventionand should not to be construed as limiting its scope.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is an elevation view of a cockpit door including a preferredembodiment of a door locking system in accordance with the presentinvention as viewed from the cabin of an aircraft;

FIG. 2 is an elevation view of the cockpit door of FIG. 1, including thedoor locking system of a preferred embodiment of the present invention,as viewed from the cockpit of an aircraft;

FIG. 3 is a detailed elevation view of the door locking system shown inFIG. 1;

FIG. 4 is a detailed elevation view of the door locking system shown inFIG. 2;

FIG. 5 is a sectioned elevation view taken at Section 5 of FIG. 3showing the latch and dead bolts and the interconnection between thesolenoid and the latch;

FIG. 6 is a sectioned elevation view taken at Section 6 of FIG. 3showing the monitor and the camera lens in the microphone on both sidesof the cockpit door;

FIG. 7A is a side elevation view taken at Section 7 of FIG. 4identifying an L-shaped striker plate having apertures for both a latchand a dead bolt and power contact points for electrical connectionbetween a door jam and the door locking system of the present invention;

FIG. 7B is a side elevation view of FIG. 7A identifying the power wiresconnected to each of the power contact points;

FIG. 7C is a top plan view of the L-shaped striker plate of FIG. 7A;

FIG. 8A is an elevation view of a flat striker plate embodiment of thepresent invention;

FIG. 8B is a side elevation view of the flat striker plate of FIG. 8Afurther showing rectangular power contact points and the power wiresconnected to the contact points;

FIG. 8C is a top plan view of the flat striker plate of FIG. 8A;

FIG. 9 is an elevation view of a door access panel of a preferredembodiment of the present invention mounted on an aircraft cockpitpanel;

FIG. 10 is a schematic of the major components for a preferredembodiment of a door locking system of the invention; and

FIG. 11 is a block diagram identifying the operational steps to operatea door locking system of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 and 2, a cockpit door 10 includes a door lockingsystem (DLS) 12 of the present invention. FIG. 1 provides a view of thecockpit door 10 looking forward from the cabin area of an aircraft. Amain cabin panel 14 replaces the door knob/lock known in the art. Asecondary cabin panel 16 is also provided above the main cabin panel 14.FIG. 2 provides a view of the cockpit door 10 looking aft from thecockpit spaces showing a main cockpit panel 18 which interconnectsthrough the cockpit door 10 with the main cabin panel 14. A secondarycockpit panel 20 interconnects through the cockpit door 10 with thesecondary cabin panel 16. A latch 22 (shown in an extended and lockedposition) extends from the DLS 12 to engage within a suitable recesswithin a door frame 24. When extended, the latch 22 provides a positivemeans to close and/or lock the cockpit door 10. In a retracted/unlatchedposition for the latch 22 (shown in phantom in FIG. 3), the cockpit door10 is free to rotate about a hinge 26. For the embodiment shown in FIGS.1 and 2, a portion of the main cabin panel 14 overlaps the door frame 24therefore permitting the cockpit door 10 to open in an aft onlydirection. By slightly overlapping the main cabin panel 14, unauthorizedaccess to attempt to displace the latch 22 is prevented.

FIG. 1 also shows an access panel 31 which is known in the art. Theaccess panel 31 can be used as an overpressure plug which permitsequalization of pressure on both sides of the cockpit door 10 in theevent of a rapid depressurization. The cockpit door 10 shown is depictedas a left handed door (i.e., hinged on the right in FIG. 1). The DLS 12can also be used on a right handed door (i.e., hinged on the left).

Referring now to FIG. 3, the portion of the DLS 12 shown in FIG. 1 isfurther detailed. The main cabin panel 14 includes an overlap portion 28which extends beyond the door edge 29 by a panel overlap dimension A.Panel overlap dimension A can be varied depending upon the thickness ofthe cockpit door 10 and the available access to the latch 22 at theoverlap portion 28.

A latch handle 30 is shown in its biased latched position. A springmeans (not shown) biases the latch handle 30 in the biased latchingdirection B as shown. A latch handle open position C, shown in phantom,is achieved by manually sliding the latch handle 30 against the tensionof the spring means. The latch handle 30 is connected to a latch lever32 which in turn connects to the latch 22 to displace the latch 22between its extended position (shown) in its retracted position (shownin phantom). In a preferred embodiment, the latch handle 30 includes arecess between the latch handle 30 and the main cabin panel 14 such thatan operator reaches within the recess and therefore within the enclosureof the main cabin panel 14 in order to access the latch handle 30 formanual operation. By providing a recess for the latch handle 30, theextension of the latch handle 30 above the surface of the main cabinpanel 14 is minimized and therefore the ability to damage or dislodgethe latch handle 30 is reduced.

The main cabin panel 14 also includes a key lock assembly 34 having akey slot 36 for insertion of a mechanical key (shown in FIG. 5). Themechanical key when placed in the key slot 36 provides the capability ofinitiating an unlock procedure of the DLS 12 when power is supplied tothe DLS 12 or manually unlocking the DLS 12 when power is unavailable tothe system. The key is normally stowed in a secured area in thepassenger cabin of an aircraft. An electronic keypad 38 is also shown.The electronic keypad 38 includes a plurality of depressible keys 40 forentering a security code to unlock the DLS 12. As soon as one of thedepressible keys 40 is depressed, an in-process light 42 illuminates,indicating that the system is energized and is ready to accept theaccess code from the user. If a valid access code is entered using thedepressible keys 40, cockpit personnel have an option to admit or denyadmission, which is discussed further herein. An OK-to-access light 44illuminates if authority to enter is provided. If an improper accesscode is entered, or by selection of one of the cockpit crew to denyaccess to the operator, an access denied light 46 illuminates. Afterentering the predetermined number of digits for the access code, theoperator presses an enter/clear button 48 to enter the data into the DLS12. An emergency button 50 is also provided for an operator to identifyan emergency situation to members of the cockpit crew. The secondarycabin panel 16 provides a microphone 52, a speaker 54, and a camera lens56. The operator can speak to cockpit crew in the cockpit area byspeaking into the microphone 52 and can hear a reply through the speaker54. The camera lens 56 provides an image of the operator standing at thecockpit door 10 to personnel in the cockpit area via a monitor shown anddescribed in reference to FIG. 4.

Electrical power is provided to the DLS 12 by a plurality of powercontact points 58. In a preferred embodiment, a power source (discussedin reference to FIG. 10) provides direct current power through two powercontact points 58. The power contact points 58 provide amechanical/electrical connection between the DLS system 12 and the powersource through similar mechanical/electrical connectors provided on thedoor frame 24 (discussed in reference to FIGS. 7A through 8B). The powercontact points 58 are preferably deflectable using a spring biasingsystem such that closure of the cockpit door depresses each of the powercontact points 58 and a spring bias ensures electrical contact ismaintained when the cockpit door is in a closed position.

In another preferred embodiment of the present invention, power contactpoints 60 are used to provide electrical power to the portion of the DLS12 mounted on the cockpit door 10. The power contact points 60 areconnected to a hinge edge 62 of the cockpit door 10 and the powercontact points 60 electrically connect to contact areas on a frame panel64 of the door frame 24. Similar to the power contact points 58, thepower contact points 60 are preferably deflectable using a springbiasing mechanism (not shown) to ensure electrical contact.

Referring to FIG. 4, the DLS 12 as viewed from the cockpit side of thecockpit door 10 is further detailed. In another preferred embodiment ofthe present invention, the main cockpit panel 18 provides a sliding deadbolt 66 actuated by a dead bolt knob 68. The dead bolt knob 68 slides inthe dead bolt slide direction D from a normally open position E to thelocked position shown in FIG. 4 by manual displacement of the dead boltknob 68. The dead bolt knob 68 and the dead bolt 66 provide anadditional security level for the cockpit door 10 in the event of anemergency situation. The dead bolt knob 68 translates within a slot 70provided in the main cockpit panel 18 for this purpose. The latch 22 isalso shown in its extended and locked position. An access use panel 72provides visual and audible indication to personnel in the cockpit areaof an aircraft of an operator on the cabin side of the cockpit door 10attempting to enter an access code to open the cockpit door 10, or usinga key to manually open the cockpit door 10. If an attempt to use a keyin the key lock assembly 34 shown in FIG. 3 is made, a manual key-uselight 74 is illuminated. A speaker 76 sounds a chime or similardistinguishable audible signal to cockpit crew of either entry of anaccess code or manual insertion of a key. A special indicator light 78illuminates if personnel in the cabin spaces of an aircraft identify aspecial condition exists in the cabin area. An emergency indicator light80 illuminates if an operator in the cabin of the aircraft depresses theemergency button 50 on the main cabin panel 14. Similarly, an electronickey pad indicator 82 is provided on the access use panel 72. Theelectronic key pad indicator 82 illuminates when a user enters one ormore numbers on the electronic key pad 38 shown in FIG. 3.

The secondary cockpit panel 20 provides a microphone 84, a speaker 86, amonitor 88, and a cabin view button 90, respectively. The microphone 84permits cockpit personnel to converse with an operator standing at thecabin side of the cockpit door 10. The speaker 86 allows cockpitpersonnel to hear the operator standing at the aft side of the cockpitdoor 10. The monitor 88 operates either by manual selection orautomatically. The monitor 88 provides a visual image of the operator orthe space adjacent to the cabin side of the cockpit door 10 whenmanually selected by depressing the cabin view button 90. Personnel inthe cockpit spaces can also depress the cabin view button 90 to get ageneral view of the cabin spaces if no operator is present beforeunlocking the cockpit door 10 for any other reason. The monitor 88 alsoautomatically operates when either an access code is entered or a key isturned in the key lock assembly 34 on the main cabin panel 14. The imagefor the monitor 88 is provided by the camera lens 56 identified in FIG.3. Electrical power for the secondary cockpit panel 20 components isprovided from the DLS 12 via wiring disposed in an electrical conduit 92positioned on the forward facing surface of the cockpit door 10 betweenthe main cockpit panel 18 and the secondary cockpit panel 20.

Referring to FIG. 5, further details of the DLS 12 are provided in asection view. A protective frame 94 joins the main cabin panel 14 to themain cockpit panel 18 via a plurality of fasteners 96 provided on thecockpit side of the cockpit door 10. Individual layers of polymer suchas Kevlar® ballistic resistant material form protective layers 98.Within the access use panel 72 is a chime 100. The audible sounds fromthe chime 100 are heard in the cockpit spaces of the aircraft via thespeaker 76 provided on the access use panel 72 shown in FIG. 4. Withinthe envelope of the cockpit door 10 a solenoid 101 is positioned. Thesolenoid 101 includes a solenoid shaft 102 which is shown in a fullyextended position engaging with a shaft recess 103 of the latch 22. Whenthe solenoid shaft 102 engages the shaft recess 103, the latch 22 ismechanically and electrically retained in the fully extended and lockedposition shown in FIG. 1. A key 104 is shown engaging the key lockassembly 34. By manually rotating the key 104, a request to enter signalis passed to the DLS 12. This request to enter signal is similar to thesignal generated when a proper access code is entered into theelectronic key pad 38. If no power is available to the DLS 12 when thekey 104 is rotated, the key lock assembly 34 acts to disengage thesolenoid shaft 102 from the shaft recess 103 thus permitting the latch22 to be disengaged from its extended and locked position by the latchhandle 30. If power is available to the solenoid 101, actuation of thekey 104 does not dislodge the solenoid shaft 102; therefore, action bycockpit personnel is required to authorize entry by providing apermission signal to open the cockpit door 10.

The protective frame 94 joins many of the DLS 12 component partsincluding the main cabin panel 14 to the main cockpit panel 18. Theprotective frame 94 also provides physical protection against damage forthe electronic components of the DLS 12 by impacting adjacent equipmentbefore the electronic components impact the adjacent equipment. Thefasteners 96 are positioned only on the cockpit side of the cockpit door10 such that removal of the fasteners is only accessible from thecockpit side.

Referring to FIG. 6, a cross section of the cockpit door 10 adjacent tothe monitor 88, the microphone 52, and the camera lens 56 is shown. Thecamera lens 56 is disposed in a through aperture such that it opticallyconnects the cabin side of the cockpit door 10 and the forward orcockpit side of the cockpit door 10. In a preferred embodiment, themonitor 88 includes a diagonal dimension between approximately 15 cm (6in) to approximately 18 cm (7 inches) such that an image on the monitor88 is visible to cockpit personnel in their seated positions.

Referring to FIGS. 7A, 7B, and 7C, an exemplary L-shaped striker plate105 is detailed. The L-shaped striker plate 105 is mechanically attachedto the door frame 24 using a plurality of fasteners (not shown) mountedthrough a plurality of fastener apertures 106. Latch apertures 108 areprovided as clearance openings for the latch 22 and dead bolt 66 (ifused). Power contact points 109 are aligned to contact each of the powercontact points 58 or power contact points 60 (shown in FIG. 3) toprovide electrical power to the DLS 12. Power wires 110 connect to eachof the power contact points 109 and lead to a power source which isdescribed in greater detail in reference to FIG. 10.

Referring to FIGS. 8A, 8B and 8C, another preferred embodiment for astrike plate is shown. A rectangular, flat strike plate 112 is similarlyprovided with a plurality of fastener apertures 114 to matably acceptfasteners to join the flat strike plate 112 to the door frame 24.Rectangular shaped power contact points 116 are provided with powerwires 118 to contact either the power contact points 58 or the powercontact points 60 (shown in FIG. 3).

Referring to FIG. 9, a door access panel 120 which is mounted on acockpit panel 122 is detailed. The cockpit panel 122 can be any one of aplurality of panels available in the cockpit area of an aircraft. Thedoor access panel 120 is positioned for operation by cockpit personnel.The door access panel 120 includes a manual switch 124. The manualswitch 124 is positionable in 3 positions. The manual switch 124 isnormally biased into an automatic switch position by a spring mechanism(not shown). In the automatic position shown for the manual switch 124,when an operator in the cabin attempts to input an access code or turnsa key 104 (shown in FIG. 5), an auto switch light 126 illuminates toidentify to cockpit personnel that a predetermined time period(approximately 30 seconds) is initiated during which the cockpitpersonnel can elect to permit opening the cockpit door 10 or denyopening the cockpit door 10. If the cockpit personnel elect to allowopening the cockpit door 10, the manual switch 124 is rotated to anunlock position which illuminates an unlock switch light 128 andde-energizes the solenoid 101 (shown in FIG. 5). This permits entry fromthe cabin area by disengaging the solenoid shaft 102 such that the latchhandle 30 is operable. Release of the manual switch 124 returns themanual switch 124 to the automatic position as shown. If cockpitpersonnel elect to deny access into the cockpit, the manual switch 124is rotated to a deny position and a deny switch light 130 isilluminated. In the deny position, electrical power to the solenoid 101is maintained and the cockpit door 10 remains in a locked position. Anauto unlock light 132 is illuminated any time that an operator attemptsto open the cockpit door 10. A lock fail light 134 is illuminated whenpower to the solenoid 101 and the DLS 12 is unavailable.

Turning now to the operation of the DLS 12, immediately subsequent tothe cockpit door 10 closing, the latch handle 30 is spring biased to aclosed position (shown in FIG. 1) and the DLS 12 automatically providespower to the solenoid 101 to engage the latch 22 by displacing thesolenoid shaft 102 into the shaft recess 103. This position for thesolenoid shaft 102 causes the latch 22 to be retained in a lockedposition (as shown in FIG. 1). In this position, the latch 22 is notaffected by either a power loss or temporary interruption to the DLS 12,and remains in the locked position during a power loss to the solenoid101. At any time a user, such as a cabin crew member, can enter anaccess code into the electronic key pad 38. The electronic key pad 38 isactuated by depressing each of a plurality of depressible keys 40 inappropriate sequence indicating a proper access code followed bypressing the enter/clear button 48. The number of digits in a validaccess code can vary and is preferably in a range between 4 to 6numbers. It should be appreciated that any type of electronic inputdevice could be implemented in lieu of a keypad and the presentinvention is therefore not limited to only the use of the electronic keypad 38 as an input device. Any form of personnel identification means(e.g., magnetic card, fingerprint identification, etc.) or a remotetransmission device (not shown) can also be used to input the accesscode.

Referring to FIG. 10, power to the DLS 12 is provided by a 28 volt DCpower source 140 associated with the aircraft. The power wires 110connect the 28 volt DC power source 140 to the power contact points 58.As evident from FIG. 10, if the cockpit door 10 is in an open positionand the power contact points 58 do not contact with their associatedpower contact points 109 (shown in FIG. 7B) or do not contact with thepower contact points 116 shown in FIG. 8B, power from the 28 volt DCpower source 140 is disconnected from the DLS 12. From the power contactpoints 58, 28 volt DC power is provided to an electronic access systemmodule (EASM) 142. The EASM contains a stored version of the access codein a memory unit 144 of the EASM 142. When an access code is entered bya user, the EASM 142 compares the entered access code to the access codestored in the memory unit 144 and identifies if a match exists. If amatch exists, power is transferred along a power line 146 to the EASMand is distributed along one of a plurality of power lines 148 toindividual components of the DLS 12. As shown in FIG. 10, the individualcomponents of the DLS 12 include the manual switch 124, the monitor 88,the camera lens 56, the microphone 52, the microphone 84, the solenoid101, the key lock assembly 34, and the electronic key pad 38. The EASM142 provides power to the solenoid 101 to withdraw the solenoid shaft102 from its extended position preventing opening of the cockpit door 10as discussed in reference to FIG. 5. Each of the connected components ofthe DLS 12 are connected to a second side of the 28 volt DC power source140 by power lines 150.

In the event of a power shortage, a cabin crew member may still gainaccess to the cockpit area via the key lock assembly 34. The key lockassembly 34 provides the ability to manually actuate the solenoid shaft102 to displace the solenoid shaft 102 from its contact position withthe latch 22.

Referring to FIG. 11, the operational steps to use the DLS 12 aredescribed. At a step 160, an operator on the cabin side of the cockpitdoor enters an access code into the electronic keyboard. When the accesscode is entered and the enter/clear button is depressed, several eventsoccur simultaneously. The in-process light on the electronic keyboardilluminates after the enter/clear button is depressed. The electronickeypad indicator on the cockpit side of the cockpit door illuminates toindicate that an entry has been made into the electronic key pad. Achime sounds in the cockpit area via the speaker 76 in the access usepanel and a 30 second operational period begins to count downautomatically. At a step 162, when the access code is entered into theelectronic key pad, the EASM energizes the monitor and the monitordepicts on its screen the image taken through the camera lens of thearea immediately adjacent to the cockpit door. At a step 164 the EASMcompares the entered code to the preset code in its memory unit toidentify if a match exists. If a match exists, at a step 166 the autounlock light is illuminated on the door access panel attached to thecockpit panel.

As further described in FIG. 11, at a step 168, the cockpit personnelhave a predetermined amount of time (approximately 30 seconds) to electto unlock the cockpit door or deny access to the cockpit. During thisperiod of time the personnel in the cockpit can rotate the manual switchon the door access panel to the unlock position, or they can choose torotate the manual switch to the deny position on the door access panel.At a step 170, if the unlock position of the manual switch is selected,the OK-to-access light illuminates on the electronic key pad. At aparallel step 172, if the manual switch is not rotated to either theunlock or the deny positions for the period of 30 seconds, the EASMafter 30 seconds automatically repositions the solenoid to permitopening of the cockpit door and the OK-to-access light illuminates onthe electronic key pad. At an opening step 174, after the OK-to-accesslight is illuminated on the electronic keypad, an operator on the cabinside manually slides the latch handle to unlock and open the cockpitdoor.

At a step 176, which parallels the step 166, the EASM determines that nomatch exists to the entered access code. At a step 178, which parallelsthe step 168, the deny position for the manual switch 124 is selected.At a step 180, which follows either the step 176 or the step 178, theaccess denied light 46 is illuminated on the main cabin panel 14, thesolenoid 101 position is unchanged and the cockpit door 10 cannot beopened.

An alternate method to open the cockpit door 10 provides that the key104 can be inserted into the key lock assembly 34 and turned. When thekey 104 is turned it provides a similar electronic signal to that sentwhen an operator enters an access code into the electronic key pad 38.Cockpit personnel have the option of unlocking the cockpit door 10 or todeny opening the cockpit door 10 using the manual switch 124 asdescribed above. The chime 100 also sounds in the cockpit area when thekey 104 is rotated in the key lock assembly 34, therefore audiblyidentifying that an attempt is being made to open the cockpit door 10.The manual key use light 74 illuminates on the access use panel 72 whenthe key 104 is rotated.

If cockpit personnel elect to deny access into the cockpit area androtate the manual switch 124 on the door access panel 120 to the denyposition, the access denied light 46 on the electronic key pad 38illuminates indicating to the user that the cockpit door 10 cannot beopened using the latch handle 30. If cockpit personnel are incapacitatedand the manual switch 124 is in the normal automatic position, a 30second wait period applies after entry of a valid access code oroperation of the key 104 before the operator receives the OK to accesslight 44 signal to open the cockpit door 10.

At any time during operation of the aircraft when cockpit personnel needto open the cockpit door 10, a visual inspection of the cabin via themonitor 88 is obtainable by depressing the cabin view button 90 on thesecondary cockpit panel 20. Depressing the cabin view button 90 displaysa view of the cabin area immediately adjacent to the cockpit door 10.This enables cockpit personnel to identify if an unsafe condition existsprior to opening the cockpit door 10. At any time when cockpit personnelidentify that an emergency situation exists on the cabin side of thecockpit door, the dead bolt 66 can be manually positioned to lock thecockpit door 10. The dead bolt 66 is not controlled by the solenoid 101and therefore the cockpit door 10 cannot be opened with the dead bolt 66in its extended, (i.e., locked) position. The dead bolt 66 is anoptional feature since it overrides the electrical features of the doorlocking system 12 of the present invention. Cockpit personnel can openthe cockpit door 10 by positioning the manual switch 124 to the unlockposition and operating the latch handle 30 on the main cockpit panel 18.If power is unavailable to the DLS 12, personnel in the cockpit (i.e.,flight crew or maintenance personnel) can operate the latch handle 30which from the cockpit side overrides the solenoid 101.

In another preferred embodiment of the present invention, Specific timeperiods are used for DLS 12 operation. If a cabin crew member enters avalid access code and the cockpit personnel take no action to repositionthe manual switch 124 for a first fixed period of time (in a preferredembodiment, approximately 30 seconds), the EASM 142 repositions thesolenoid shaft 102 automatically after the first fixed period of time.Subsequent to the first fixed period of time, a user can manipulate thelatch handle 30 to displace the latch 22 for a second fixed period oftime (in a preferred embodiment, approximately 30 seconds). If the userfails to displace the latch handle 30 within the second fixed period oftime, the EASM 142 automatically returns the solenoid shaft 102 to itsengaged position with the latch 22, preventing opening of the cockpitdoor 10. The first and second fixed periods of time are described hereinas approximately 30 seconds; however any period of time can be selectedby the aircraft designer or the aircraft operators.

The electromechanical architecture of the DLS 12 of the presentinvention provides numerous advantages over prior systems. First, thearchitecture provides graphical identification that a user seeks accessto the cockpit area, thereafter enabling cockpit personnel to grantaccess, deny access, or allow the DLS 12 to continue in an automaticmode. The architecture also provides the advantage of maintaining thecockpit door in its locked position in the event of a power shortage.The DLS 12 further includes a mechanical key mechanism to lock andunlock the cockpit door in the event of a power shortage or if theaccess code is unavailable to an operator on the cabin side of thecockpit door. The DLS 12 of the present invention further advantageouslyprovides that electrical power for the system is provided throughcontacts at the cockpit door such that system power is disconnected whenthe door is in an open position and is connected while the cockpit dooris in its closed and/or locked position. The use of power contact pointsbetween the door structure and the door locking system 12 of the presentinvention eliminates the need for flexible wiring or a more complexsystem of providing electrical power to the door locking system 12 ofthe present invention.

1. A method of electronically controlling access to a restricted area ofa mobile platform separated from a non-restricted area by a door, thedoor having a door locking system, said method comprising: locking thedoor using the door locking system with electrical power available tothe door locking system; entering an access code indicating anauthorized entry into the restricted area; initiating a predeterminedtime interval delay after entry of the access code before the doorlocking system can be unlocked.
 2. The method of claim 1, furthercomprising automatically unlocking the door locking system following thepredetermined time interval delay.
 3. The method of claim 2, wherein thestep of automatically unlocking the door locking system furthercomprises enabling a control panel to automatically unlock the flightdeck door locking system.
 4. The method of claim 3, further comprising:setting the predetermined time interval delay to a first fixed period oftime; and automatically relocking the flight deck door locking systemsubsequent to a second fixed period of time if a first user fails toopen the door within the second fixed period of time.
 5. The method ofclaim 1, further comprising: setting the predetermined time intervaldelay to a first fixed period of time; automatically locking the flightdeck door locking system subsequent to a second fixed period of time ifa first user fails to open the door within the second fixed period oftime; and enabling entry of an additional access control feature intothe door locking system by a second user located in the restricted area,the additional access control feature operable to disable the doorlocking system from unlocking the door.
 6. The method of claim 5,further comprising limiting entry by the second user of the additionalaccess control feature to within the first period of time.
 7. The methodof claim 1, further comprising disposing a user input device on anon-restricted area side of the door.
 8. The method of claim 7, furthercomprising creating a camera image of an area adjacent to the user inputdevice upon receipt of the access code.
 9. The method of claim 1,further comprising enabling manipulation of a mechanism of the doorlocking system with a key to unlock the door locking system.
 10. Amethod of controlling access to a restricted area of a mobile platformseparated from a non-restricted area by a door, the door having anelectronic door locking system, the method comprising: locking the doorusing the door locking system with electrical power available to thedoor locking system; manipulating a mechanism of the door locking systemwith a key; and automatically unlocking the door locking systemfollowing a predetermined time interval after the manipulating step. 11.The method of claim 10, wherein the step of automatically unlocking thedoor locking system further comprises enabling a control panel toperform the automatic unlocking step subsequent to a first fixed periodof the predetermined time interval.
 12. The method of claim 11, furthercomprising automatically locking the flight deck door locking systemsubsequent to a second fixed period of time if a first user fails toopen the door within the second fixed period of time.
 13. The method ofclaim 10, further comprising: setting the predetermined time intervaldelay to a first fixed period of time; automatically locking the flightdeck door locking system subsequent to a second fixed period of time ifa first user fails to open the door within the second fixed period oftime; and enabling entry of an additional access control feature intothe door locking system by a second user located in the restricted area,the additional access control feature operable to disable a change inlock condition of door locking system.
 14. The method of claim 13,further comprising limiting entry by the second user of the additionalaccess control feature to within the first period of time.
 15. A methodof controlling access to a restricted area of a mobile platformseparated from a non-restricted area by a door having a locking system,the door locking system including an electronic control panel, a userinput device and a camera lens, the method comprising: supplyingelectrical power to the electronic control panel for controlling thedoor locking system; inputting an access code for unlocking the doorlocking system; producing an image of an area adjacent to the user inputdevice using the camera lens upon receipt of the access code; anddisposing a locking assembly having a locking component on the door, thelocking assembly being responsive to the electronic control panel forautomatically actuating the locking component.
 16. The method of claim15, further comprising operating a mechanical key lock assembly to urgethe locking component into an unlocked position in the event of a powershortage to the door locking system.
 17. The method of claim 15, furthercomprising inputting a code into the user input device using anelectronic keypad.
 18. The method of claim 15, further comprisingmanually latching the door to prevent the door from being opened. 19.The method of claim 15, further comprising manually actuating a switchremotely positioned from the door in the restricted area to position thelocking component between one of an unlock position operable to positionthe locking component in an unlocked condition and a deny positionoperable to maintain the locking component in a locked condition. 20.The method of claim 15, further comprising manually selecting to displayan image of the camera lens by an operator in the restricted area. 21.The method of claim 15, further comprising enabling an audio message tobe addressed to an operator in the restricted area from thenon-restricted area operable to alert the operator that a user has inputan access code into the user input device.